* OGP was only source of China crude oil inventories data
* No word on why data was withdrawn
* Market left with only one sporadic source on fuel stocks
BEIJING, Nov 3 (Reuters) - China OGP, an oil industry newsletter issued by Xinhua news agency, will no longer publish data on China's stockpiles of crude oil, gasoline and diesel, it said on Tuesday.
The move removes the only public source of information on Chinese crude and fuel stockpiles, key information for oil traders trying to assess the real level of demand in China, the world's second-biggest oil consumer.
"China OGP will halt the release of China's crude oil, gasoline and diesel stockpiles held by CNPC and Sinopec Group because these figures are no longer available," a brief note at the start of the biweekly newsletter said.
It did not explain further or say if it had been ordered to withhold the information or whether the publication of the data might resume in future.
OGP's data, which was sourced from China's top state oil firm CNPC, showed inventories for CNPC and state refining giant Sinopec. Although the data was partial, it provided a proxy for the whole Chinese commercial market because the two companies are so dominant.
It also included the state's strategic crude reserve, which is likely to have been unchanged this year because China has filled its existing tanks and has not yet built new ones.
The other chief source of information on commercial fuel stocks is the China Petroleum and Chemical Industry Association, which does not issue data publicly and does not cover crude oil or strategic reserves. Its figures are occasionally reported in the Chinese media.
One foreign oil market forecaster, who declined to be identified, said OGP's decision would make it much harder to tell what was happening to China's oil demand.
"It's a shame, he said. "It does give you a better picture.
"For example, before the Olympics, there was clearly a huge stockbuild, which one can only assume was deliberate. When we were talking about huge demand, quite a lot of it was due to stockpiling.
"And earlier this year, demand seemed to be falling but actually it was due to destocking."
The data in Xinhua's OGP newsletter, which was sourced from state oil firm CNPC, goes back to January 2008. To see a graph of crude oil inventories based on OGP's data, please click here
Last month's newsletter also radically revised historical diesel and gasoline figures, causing many analysts to reassess their calculations. For a graphic of the revised data, which showed big increases over previous figures, please click here
The oil forecaster said the revision did not alter the month-on-month changes, suggesting that the data had been compiled by applying a stockdraw or build to the previous figure.
To read more stories about Chinese oil and fuel stocks, please click on [O/CNSTOCKS]. (Editing by Chris Lewis)